Plasma display panels (PDP), as used in high definition televisions (HDTV) and projection television (PTV) applications, conventionally use manganese activated zinc silicate phosphor as a green emitting component due to its availability and high quantum efficiency. However, compared with red and blue emitting phosphors, zinc silicate exhibits a wide spectrum of emission with low color purity, long persistence and fast saturation with vacuum ultra violet (VUV) flux. Therefore, many efforts have been made to develop a phosphor that provides improved performance characteristics and can be used to replace Mn activated zinc silicate.
In addition, the red phosphor, green phosphor and blue phosphor currently used in PDP's have different physical characteristics and each requires a different phosphor paste rheology and screening process. Also, after screening, these phosphors exhibit different optical and electrical characteristics. These different characteristics affect the design and performance of the display. Therefore, to provide for compatible physical characteristics, it would be advantageous to form all three phosphors from a common host material that exhibits suitable red, green and blue emission under Xenon plasma excitation.
HDTV and similar types of display devices should have high resolution and high brightness for better performance. This can be achieved only with thin phosphor screens formed with very small phosphor particles (1-2 microns) in a close rib structure. Screens with small particles have a higher packing density and also require a lower binder content. HDTV and other such devices also require phosphors to display short persistence (between 5 and 10 ms) in order to prevent the formation of ghost images. It is known that lanthanide borates provide high quantum efficiency, good stability at operating temperatures and long life time with various activators, coactivators and sensitizers, particularly under VUV excitation. However, very limited information is available on the preparation and luminescence of lanthanide borates, and particularly, rare earth (RE) activated yttrium borate and yttrium gadolinium borate phosphors.